I'm in the process of deploying the Solana helloworld example smart contract on Ubuntu 20.04. When running npm run build:program-rust, the package.json in the root of the repository states that this corresponds with cargo build-bpf --manifest-path=./src/program-rust/Cargo.toml --bpf-out-dir=dist/program. However, when running this command compilation is stuck without any indicators, even when appending the verbosity tag to the cargo build command.

I have a fresh installation of Ubuntu 20.04 and only took the following steps:

  • sudo apt update && sudo apt upgrade
  • Install NodeJS v14.x and build-essential
  • Install Rust: curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
  • Install Solana CLI: sh -c "$(curl -sSfL https://release.solana.com/v1.8.6/install)"
  • git clone https://github.com/solana-labs/example-helloworld.git

When running which cargo-build-bpf, Ubuntu points towards the directory ~/.local/share/solana/install/releases/1.8.6/solana-release/bin/cargo-build-bpf, indicating that the PATH variable has been updated correctly.

The Cargo.toml file looks as follows:

name = "solana-bpf-helloworld"
version = "0.0.1"
description = "Example template program written in Rust"
authors = ["Solana Maintainers <[email protected]>"]
repository = "https://github.com/solana-labs/solana"
license = "Apache-2.0"
homepage = "https://solana.com/"
edition = "2018"

no-entrypoint = []

borsh = "0.9.3"
borsh-derive = "0.9.1"
solana-program = "~1.10.35"

solana-program-test = "~1.10.35"
solana-sdk = "~1.10.35"

name = "helloworld"
crate-type = ["cdylib", "lib"]

Yesterday, I tried deleting the Cargo.lock file and run cargo update. It got stuck in trying to retrieve the Borsh crate which is also specified in the Cargo.toml file. I don't exactly know the relevance of this, but it seems worth pointing out.

2 Answers 2


I went out tonight and left the command running. When I came back, I was delighted to be greeted with an error message:

error: Unable to update registry `crates-io`

    Caused by:
      failed to fetch `https://github.com/rust-lang/crates.io-index`

    Caused by:
      network failure seems to have happened
      if a proxy or similar is necessary `net.git-fetch-with-cli` may help here

    Caused by:
      SSL error: received early EOF; class=Ssl (16); code=Eof (-20)

This issue was mentioned here and while still open, the workaround did the trick for me. Simply set the mentioned environment variable to true as follows:


I will accept my own answer when I'm allowed to do so (in two days).


I was able to solve the problem after long hours

  1. First you need to resolve the network problem allowing the system to reach full 100%.
  • Using the external git system is more stable than using the one that is build in


Add this to your ~/.bashrc file and restart the terminal

This will switch to the external git

  1. Now increase the GIT Timeouts for slower connections

git config --global http.lowSpeedLimit 1000

git config --global http.lowSpeedTime 60

this will make GIT be very patient when downloading and dont stop easily on timeots

  1. Delete cache-inconsistencies

Once your download is reaching 100% but still failing you have to delete everythin in

cd ~/.cargo/registry

enter into this folder and use rm -rf * to delete all files and subfolders there

Once the folder is completely empty run

cargo build-bpf

This will then finally work

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